KR101989887B1 - Coupling with projections having angularly oriented surface portions - Google Patents

Abstract

The mechanical coupling for connecting the pipe elements has an end-to-end segment, each segment being arranged about the ring gasket in spaced relation, so as to act as a guide for insertion of the pipe element between the segments, And has protrusions with angled surface portions. A method of assembling a pipe joint includes engaging a surface with an end of the pipe element and rotating the segments relative to each other to permit insertion.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a coupling having projections with angled surface portions,

Cross-reference to related application

This application claims priority to U.S. Patent Application No. 13 / 300,756, filed November 21, 2011, the entirety of which is hereby incorporated by reference.

Field of invention

The present invention relates to a pipe coupling for connecting pipe elements in an end to end relation.

The mechanical coupling for end-to-end connection of the pipe elements together includes an interconnectable segment circumferentially surrounding the end portion of the coaxially aligned pipe element. The term "pipe element" is used herein to describe any pipe-like item or component having a pipe-like shape. The pipe elements include control components such as valves, reducers, strainer, restrictors, pressure regulators, etc., as well as pipe fittings such as pipe stock, tee, cap and elbow.

Each mechanical coupling segment includes a housing extending radially inwardly from the housing, for example, with a protrusion engaging the outer surface of the plane end pipe element, the pipe element having a circumferential Grooves, or shoulders and beads. The engagement between the projection and the pipe element provides mechanical restraint to the joint and ensures that the pipe element remains balanced and balanced under high internal pressure and external forces. The housing defines an annular channel or pocket that receives a gasket or seal, typically a resilient ring, that engages the end of each pipe element and cooperates with the segment and the pipe element to provide a fluid-tight seal. The segment typically has a lug-shaped connecting member projecting outwardly from the housing. The lugs are adapted to accommodate fasteners such as nuts and bolts that can be adjustably tightened to pull the segments toward each other.

The protrusions on the prior art coupling typically have an arcuate surface with a radius of curvature that substantially matches the radius of curvature of the outer surface of the pipe element being engaged. For a coupling used with a grooved pipe element, the radius of curvature of the arcuate surface is smaller than the radius of curvature of the outer surface of the outer pipe element of the groove so that the arcuate surface fits into the groove.

The method of securing the pipe element in an end-to-end relationship includes a sequential installation process when mechanical coupling according to the prior art is used. Typically, the engineer receives the coupling while the segments are bolted together and the ring gasket is trapped in the channel of the segment. The engineer first disassembles the coupling by releasing the bolt engagement, removes the ring seal, lubricates it (if not pre-lubricated) and places it around the end of the pipe element to be connected. The installation of the ring gasket often requires that it be lubricated and stretched to accommodate the pipe element. The ring gasket remains in place on both pipe elements, after which the segments sit on the ends of the pipe element and place the ring gaskets against them one by one, one at a time. During the laying, the segments engage the gasket, the projections align with the grooves, the bolts are inserted through the lugs, the nuts are screwed onto the bolts, the coupling segments are pulled toward each other, the gaskets are compressed Engages with the protrusion in the groove.

As is apparent from the foregoing description, the installation of mechanical pipe couplings in accordance with the prior art typically requires the use of a couple of couplings while the engineer is handling at least seven individual piece parts (and further coupling has more than two segments) It is required to completely disassemble and reassemble the ring. Significant time, effort, and cost will be saved if the technician can install it without disassembling the mechanical pipe coupling, piece-to-piece, first and then reassembling it completely.

Fig. 1 shows a coupling 11 with coupling segments 13,15. The segments are connected end to end by connecting members 17, 19, and the connecting member comprises a threaded fastener 21. Segments 13 and 15 are shown supported in spaced relation to each other on the outer surface of the ring gasket 23 captured between the segments. It is possible to insert the pipe element into the central space 25 between the segments without disassembling the coupling when the segments are supported in this way. However, there are some drawbacks to this solution for mechanical coupling installation problems. Note that there is a limit on the pipe element diameter tolerance that can be accepted by the coupling 11. If the pipe elements are not sufficiently rounded or their ends are extended to the maximum extent permitted by the specification, the pipe elements will not exit the protruding portions 29 extending into the central space, It will be difficult to insert it into the recess 25 and thus become impossible. Moreover, the ring gasket itself can resist insertion of the pipe element when the distortion is not controlled. Many mass-produced pipe elements are not as rounded to some extent, and roll-groove pipe elements can extend to some extent. Thus, the use of coupling 11 permits tighter tolerances on these parameters, limiting the pipe elements that can be effectively used with such coupling, and whether "selected" pipe elements within acceptable tolerances, The pipe element becomes more expensive because it must be tolerable to determine that it should be tight.

Thus, there is a need for a pipe coupling that can be used with pipe elements that have a tolerance tolerance to parameters such as non-roundness and widening, and which will allow the pipe element to be reliably inserted without disassembly of the coupling It is clear.

The present invention relates to a coupling for connecting pipe elements in an end-to-end relationship. In an exemplary embodiment, the coupling includes a plurality of segments that define a central space for end-to-end enclosing the central axis and receiving the pipe element. At least one of the segments includes a pair of protrusions that are positioned in spaced relation on opposite sides of a segment and extend toward the central axis. At least a portion of each of the projections is engageable with one of the respective ones of the pipe elements. Each of the projections has an arcuate surface opposed to the central axis. The rear wall extends between the projections. The rear wall has an arcuate surface facing the central axis.

In another example embodiment of the coupling, at least one of the projections includes first and second outwardly facing surface portions. The first surface portion is oriented at an angle relative to the second surface portion. The first surface portion may be at an angle of about 35 [deg.] To about 60 [deg.] As measured relative to the central axis. The first surface portion is centered on a line extending from the central axis and is at an angle of about 30 [deg.] To about 50 [deg.] Measured from the first line extending between the first end of one segment and the second end of one segment May be oriented. The first surface portion may have a directivity angle of about 15 [deg.] To about 60 [deg.] Relative to the second surface portion. In this example embodiment, one protrusion may further include a third outwardly facing surface portion. The third surface portion is oriented at an angle relative to the second surface portion. The third surface portion faces an angle of about 35 [deg.] To about 60 [deg.] As measured relative to the central axis. The second surface portion is positioned between the first and third surface portions. The third surface portion is centered on a line extending from the central axis and oriented at an angle of about 30 [deg.] To about 50 [deg.] As measured from the first line. The third surface portion may have a directivity angle of about 15 [deg.] To about 60 [deg.] Relative to the second surface portion.

At least one notch can be positioned in at least one of the protrusions, and the notch is located at the end of one segment. In an exemplary embodiment, the at least one notch includes first and second notches positioned on opposite ends of a segment.

In a specific example embodiment of the coupling according to the present invention, only the first and second segments of the segments are end-to-end and surround the central axis. The coupling further includes a ring gasket positioned between the first and second segments. The ring gasket supports the first and second segments in a spaced apart relationship sufficient to insert the pipe element between the segments. The first and second segments have side walls from which protrusions extend. The projections and the rear wall of each segment cooperate to define a pocket for receiving the ring gasket.

The present invention also encompasses the segments used in the coupling to connect the pipe elements in an end-to-end relationship. The coupling includes a plurality of segments that define an end-to-end spaced-apart central space for receiving the pipe element and surrounding the central axis. In an exemplary embodiment, the segments include a pair of projections positioned in spaced relation on opposite sides of the segment. The protrusions extend toward the central axis. At least a portion of each of the projections is engageable with one of the respective ones of the pipe elements. Each of the projections has an arcuate surface opposed to the central axis. The rear wall extends between the projections. The rear wall has an arcuate surface facing the central axis.

In an exemplary embodiment according to the present invention, at least one of the projections includes first and second outwardly facing surface portions. The first surface portion is oriented at an angle relative to the second surface portion. The first surface portion may be at an angle of about 35 [deg.] To about 60 [deg.] As measured relative to the central axis. The first surface portion is centered on a line extending from the central axis and is at an angle of about 30 [deg.] To about 50 [deg.] Measured from the first line extending between the first end of one segment and the second end of one segment Lt; / RTI > The first surface portion may have a directivity angle of about 15 [deg.] To about 60 [deg.] Relative to the second surface portion. The protrusion may further include a third outwardly facing surface portion. The third surface portion is oriented at an angle relative to the second surface portion. The third surface portion may correspond to an angle of about 35 [deg.] To about 60 [deg.] As measured relative to the central axis. The second surface portion is positioned between the first and third surface portions. The third surface portion may be centered on a line extending from the central axis and oriented at an angle of about 30 [deg.] To about 50 [deg.] As measured from the first line. The third surface portion may have a directivity angle of about 15 [deg.] To about 60 [deg.] Relative to the second surface portion.

In an exemplary embodiment, the segment may further include at least one notch positioned within at least one of the protrusions, wherein the notch is located at the end of the segment. The at least one notch may include first and second notches positioned on opposite ends of a segment.

The invention also includes a method for coupling the first and second pipe elements in an end-to-end relationship. In one embodiment, the method comprises:

Using a pipe coupling end-to-end attached to each other and having first and second coupling segments surrounding a central axis and defining a central space, the coupling segments being supported on the elastic ring gasket in spaced- Wherein the coupling segment has a connecting member at each end to pull the coupling segment toward the center space when the adjustable connecting member is tightened,

At least a portion of each of the projections is engageable with one of the respective ones of the pipe elements, and each of the projections has a pair of protrusions that are positioned in spaced relation on opposite sides of one coupling segment and extend toward the central axis, Has an arcuate surface facing the central axis,

Wherein at least one of the protrusions includes first and second outwardly facing surface portions, the first surface portion is oriented at an angle relative to the second surface portion, and wherein the first surface portion is about 35 Deg.] To about 60 [deg.];

Inserting a first pipe element into the central space from one side of the pipe coupling, wherein the first pipe element engages the coupling segment and thereby rotates the coupling segments relative to each other about the connecting member passage axis, Providing a clearance for inserting the element;

Inserting a second pipe element into the central space from the opposite side of the pipe coupling; And

And engaging the connecting members thereby pulling the coupling segments towards each other to engage the first and second pipe elements to join them in an end-to-end relationship.

The method includes the steps of inserting a second pipe element into the central space from the opposite side of the coupling and engaging the coupling segment thereby rotating the coupling segments relative to each other about the connecting member passage axis to insert the second pipe element And providing a clearance.

1 is an elevational view of an exemplary mechanical pipe coupling according to the present invention;
2 is an elevational view of an exemplary mechanical pipe coupling according to the present invention;
3 is a cross-sectional view of a segment of an exemplary mechanical pipe coupling according to the present invention taken at line 3-3 of FIG. 2;
Figures 4A and 4B are isometric views of segments of a mechanical pipe coupling of an example according to the present invention;
Figures 5A and 5B are elevation views of segments of a mechanical pipe coupling of an example according to the present invention; And
Figures 6 to 9 are longitudinal cross-sectional views illustrating an exemplary method of forming a pipe joint in accordance with the present invention, Figure 6 is a longitudinal cross-sectional view taken along line 6-6 of Figure 5A, Figure 7 is a cross- Sectional view taken along line 7-7 of FIG.

Figure 2 shows an embodiment of a coupling 10 according to the invention. The coupling 10 includes segments 12, 14 that define a central space 18 surrounding the central axis 16 and end-to-end with each other. The central space 18 receives the pipe element to be connected in an end-to-end relationship, and the longitudinal axis of the pipe element is substantially aligned with the central axis 16. Each of the segments 12,14 has a connecting member 20,22 at each end. In this example, the linking member includes a lug 24 that protrudes from the segment and receives a threaded fastener 26. The fasteners 26 can be adjustably tightened to pull the segments 12, 14 toward each other and towards the central axis 16 to engage the pipe elements and form a joint.

As shown in cross-section in Fig. 3, each segment (segment 12 is shown) has a pair of projections 28, 30 positioned in relation to each other on opposite sides of the segment. The protrusions extend toward the central axis 16 and at least a portion of each protrusion is engageable with the respective pipe element so as to provide mechanical engagement and to hold the pipe element in an end-to-end relationship. The protrusions 28, 30 engage, for example, with a plain surface, a surface forming a circumferential groove, a surface with a raised shoulder, or an outer surface of the pipe element, which may be a shoulder and bead. As shown in Figure 3, each projection has an arcuate surface 32 opposite the central axis 16.

Segments 12 and 14 also have sidewalls 36 and 38 through which protrusions 28 and 30 extend. The side walls 36, 38 are attached to the rear wall 40, and the side walls and the rear wall define the pockets 42 together. The rear wall 40 has an arcuate surface 44 extending between the protrusions 28 and 30 and opposed to the central axis 16. [ The pocket 42 receives a ring gasket 43 (FIG. 3) positioned between the segments 12, 14 (see FIG. 2) to ensure a fluid-tight seal.

As shown in Figs. 4A-5B, protrusions such as 28, 30 may include at least two externally facing surface portions 78, 80. In this context, "outwardly facing" means facing away from gasket pocket 42 outwardly. In this example, the surface portion 78 is oriented angled with respect to the surface portion 80.

4A and 5A the surface portion 80 is oriented at an angle relative to the outermost surface of the protrusion 28 (the surface of the protrusion 28 furthest away from the gasket pocket 42) Thereby defining an angled surface or chamfer extending between the outermost surface of the projection 28 and the arcuate surface 32 (see FIG. 3) of the projection 28. In this example, the surface portion 78 may have a relative orientation angle 82 of about 15 to about 45 degrees and may have an angle of about 35 to about 60 degrees as measured relative to the central axis 16 84). Alternatively, as shown in Figures 4B and 5B, the surface portion 80 may be angled such that the surface portion 80 extends between the outermost surface of the protrusion 28 and the arcuate surface 32 of the protrusion 28 It may correspond to the outermost surface of the projection 28 so as not to include a surface or a chamfer. In this example, the surface portion 78 may have a relative orientation angle 82 of about 15 to about 60 degrees and may have an angle of about 35 to about 60 degrees as measured relative to the central axis 16 84).

The surface portion 78 may further be centered on a line 86 extending from the central axis 16, as shown in Figs. 5A and 5B. The center line 86 of the surface portion 78 may have a measured directional angle 88 from a line 55 extending between the ends 56 and 58 of the segment 72. Orientation angle 88 can range from about 30 degrees to about 50 degrees. As shown in FIGS. 5A and 5B, the segment 72 has a third outwardly facing surface portion 90 that is oriented angled with respect to the surface portion 80. Although the range of angular orientation of the surface portion 90 with respect to the surface portion 80 may be the same as for the surface portion 78, the actual directivity angle of the surface portion 90 with respect to the particular coupling, It is not necessary that the orientation angle of surface 78 be the same, although all of such surface portions are advantageous on the segment forming the coupling.

The advantage of the angled surface portions 78, 90 is shown in Figures 6 to 9, which illustrate an exemplary method of joining a pipe element in accordance with the present invention. It is advantageous to have a coupling 73 formed of segments such as 12, 13, 14, 15, 66 or 72 that do not need to be disassembled and then reassembled around them to form a joint between the pipe elements. In the example shown in Figs. 6-9, the coupling 73 is formed of the segment 72 used as an example. Such as the coupling 10, 11, and 73, is such that the coupling segment is attached to the threaded fastener 26, as shown for the coupling 10 in FIG. 2, Is "ready to be installed" from the factory because it is supported in spaced relation on the pipe 43 to allow the pipe element to be inserted into the central space 18 without disassembling the coupling. Figure 6 illustrates the insertion of the pipe element 92 into the central space 18 of the coupling 73. Insertion is initiated by contacting the end of the pipe element 92 with the angled surface 90 on the projection 28 on the segment 72.

The surface 90 facilitates insertion by acting as a lid in the guide to center the pipe element 92 and to initiate rotation of the segment 72 around the axis 94 passing through the connecting member. The rotation of the segment is illustrated in Fig. The ring gasket 43 serves as a spring that allows the segment 72 to swing outward and to allow the pipe element 92 to enter the central space 18 due to its elasticity and elasticity. Once the pipe element 92 is sufficiently engaged with the coupling 10 in the central space 18 the elastic biasing of the ring gasket 43 causes the coupling segments 12 and 14 to move toward their original relative angular position Restore. May be defined when, for example, the projection 28 aligns with the groove 96 in the pipe element 92, or when the end of the pipe element contacts the gasket stop 98. The restoring force provided by the spring action of the ring gasket 43 allows another pipe element 100 to be inserted from the opposite side of the coupling 10, as shown in Fig. Upon insertion into the central space 18, the pipe element 100 contacts the angled surface 78 on the projection 30 of the segment 72 and the segment is moved away from the pipe element 94 ). When the pipe element 100 is sufficiently engaged with the coupling 73, a fastener (see also Fig. 2) connecting the segment 72, as shown in Fig. 9, 0.0 > 100, < / RTI > In this example, the pipe outer surface will include circumferential grooves 96, but shoulder and bead pipe elements are also feasible, along with other types of pipe elements, such as plain end, shoulder-type. 2 and 4A-5B, the notch 102 also includes protrusions 28, 30 near the ends of the segments 12, 14, 66, 72 to provide additional clearance for the insertion of the pipe elements. . ≪ / RTI > In an exemplary embodiment, the first and second notches 102 may be positioned on opposite ends of the segments 12, 14, 66, 72.

The use of angled surface portions 78, 90 allows the pipe element with the worn end to be received in the coupling 10 by the insertion method. End widening occurs when the pipe elements are cold worked by rolling to form, for example, circumferential grooves, and the expanded diameter of the widened ends is dependent on the ability of the coupling segments to rotate relative to each other about the shaft 94 and If there are no angled surface portions, there may be some difficulty in insertion. The notch 102 also helps to enable a widened pipe to be used with the method of joint assembly according to the present invention.

The use of angled surface portions 78 and 90 also allows the pipe elements not axially aligned with the central axis 16 of the coupling 10 to be easily accommodated in the central space 18. [

Figures 4A-5B illustrate another feature of the coupling according to the present invention. Figures 4A and 4B depict a rigid coupling segment 66 for use with a circumferentially grooved pipe element. The segments 66 have an interfacing surface 68, 70 having opposite angular orientation with respect to each other. When the fastener joining such segments is tightened, the interfacing surfaces 68, 70 on one segment are forced to contact their mating surfaces on the mating segment and the segments are forced to rotate about the vertical axis in a direction opposite to each other. This causes the projections 28, 30 to engage the sidewalls of the circumferential groove in the pipe element and lock them in place to provide significant resistance to the external bending force, thereby limiting the relative bending of the pipe element. Rigid couplings are disclosed in U.S. Patent No. 4,611,839 and U.S. Patent No. 4,639,020, both of which are incorporated herein by reference.

5A and 5B are segments 72 of a more flexible coupling. The interfacing surfaces 74 and 76 between the segments 66 and 72 are not angled and they do not cause any relative rotation of the segments when they are engaged with each other. Thus, the projections 28, 30 do not engage with the sidewalls of the circumferential groove due to the torsional action of the segments resulting in a softer joint, in which case the relative bending of the pipe elements during bending is twisted and axially , And greater than for rigid joints (described above) for the same applied load.

The angled oriented surfaces described above and claimed herein are applicable to both rigid and flexible couplings. Thus, the features or elements of the angled, oriented surfaces described or depicted for only one of the segments 66 or 72, or only one of the protrusions 28 or 30, may also be used for the other segment (66 or 72) And is also applicable to and included in one protrusion 28 or 30.

The pipe coupling according to the present invention requires less energy to install because it allows the non-deformation coupling to be used as a ready-to-install coupling and does not require significant energy to deform the coupling when achieving the pipe joint . This corresponds to less battery replacement when the wireless power tool is used, with less fatigue when manually forming joints with hand tools.

Claims (45)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete A method for joining first and second pipe elements in an end-to-end relationship, the method comprising:
Using a pipe coupling end-to-end attached to each other and having first and second coupling segments surrounding a central axis and defining a central space, the coupling segments being supported on the resilient ring gasket in spaced relation Wherein the coupling segment has the connecting member at each end to pull the coupling segment toward the center space when the adjustable connecting member is tightened,
And a pair of protrusions positioned in spaced relationship on opposite sides of the one coupling segment and extending toward the central axis, wherein at least a portion of each of the protrusions is engageable with one of the respective ones of the pipe elements Each of said protrusions having an arcuate surface opposite said central axis,
Wherein at least one of the protrusions includes a first outwardly facing surface portion and a second outwardly facing surface portion and wherein the first outwardly facing surface portion is angled relative to the second outwardly facing surface portion, Wherein the first outwardly facing surface portion is at an angle of 35 to 60 degrees measured relative to the central axis;
Inserting the first pipe element into the central space from one side of the pipe coupling, the first pipe element engaging the coupling segments thereby rotating the coupling segments relative to each other, Inserting the first pipe element into the central space providing a clearance for inserting the pipe element;
Inserting the second pipe element from the opposite side of the pipe coupling into the central space; And
Coupling the first and second pipe elements to the ends of the first and second pipe elements by tightening the coupling members thereby pulling the coupling segments toward each other to engage them with the first and second pipe elements to form an end- To-end relationship. 28. The method of claim 27, wherein inserting the second pipe element from the opposite side of the pipe coupling into the central space includes engaging the coupling segment with the second pipe element, And relatively rotating the first pipe element to provide a clearance for inserting the second pipe element. 28. The method of claim 27, wherein the first outwardly facing surface portion is centered on a line extending from the central axis and between a first end of the one coupling segment and a second end of the one coupling segment Wherein the first and second pipe elements are oriented at an angle of 30 to 50 degrees measured from an extending first line. 28. The method of claim 27, wherein the first outwardly facing surface portion has first and second pipe elements having an orientation angle of 15 to 60 relative to the second outwardly facing surface portion, A method for combining in a relationship. 32. The method of claim 29, wherein the at least one projection further comprises a third outwardly facing surface portion, and wherein the third outwardly facing surface portion is oriented angularly relative to the second outwardly facing surface portion Said third outwardly facing surface portion facing an angle along said projection of 35 to 60 degrees measured relative to said central axis and said second outwardly facing surface portion facing said first outward Wherein the first and second pipe elements are positioned between an opposing surface portion and a third outwardly facing surface portion. 32. The method of claim 31, wherein the third outwardly facing surface portion is centered on a line extending from the central axis and oriented at an angle of 30 to 50 degrees measured from the first line, A method for combining pipe elements into an end-to-end relationship. 32. The method of claim 31, wherein the third outwardly facing surface portion has first and second pipe elements having an orientation angle of 15 to 60 relative to the second outwardly facing surface portion, A method for combining in a relationship. 28. The apparatus of claim 27, wherein the first and second segments include sidewalls extending from the protrusions and a rear wall extending between the protrusions, the sidewalls being attached to the rear wall, the sidewalls and the rear wall Wherein the first and second pipe elements define a pocket together and the pocket is adapted to receive the elastic ring gasket. 28. The method of claim 27, wherein the pipe coupling further comprises at least one notch positioned in at least one of the protrusions of each segment, each notch positioned at one end of the segment, And a second pipe element in an end-to-end relationship. 36. A method according to claim 35, wherein the at least one notch comprises first and second notches positioned on opposite ends of the one segment, the method for joining the first and second pipe elements in an end- . 28. The method of claim 27, wherein inserting the first pipe element into the central space is performed without disassembly of the pipe coupling. 29. The method of claim 28, wherein inserting the second pipe element into the center space is performed without disassembly of the pipe coupling. 29. The method of claim 28, wherein prior to inserting the first and second pipe elements into the center space, the first and second coupling segments are disposed at their original relative angular positions, The elastic ring gasket elastically biasing resiliently biases the first and second coupling segments toward their original relative angular position, after the first and second pipe elements are inserted into the central space and the connecting member is tightened, To-end relationship. 28. The method of claim 27, wherein the first and second pipe elements each have a widened end, in an end-to-end relationship with the first and second pipe elements. 41. The method of claim 40, wherein the widened ends of the first and second pipe elements each define a circumferential groove, wherein the step of tightening the coupling member comprises: coupling the projection of each coupling segment with the first and second Wherein the first and second pipe elements engage corresponding circumferential grooves of the pipe element in an end-to-end relationship. 28. The method of claim 27, wherein prior to inserting the first and second pipe elements into the central space, the first and second pipe elements are spaced apart from each other 1 and the second pipe element in an end-to-end relationship. 28. The method according to claim 27, wherein the pipe coupling is a rigid pipe coupling, the first and second pipe elements being joined in an end-to-end relationship. 44. The method of claim 43, wherein each of said first and second coupling segments each have an interfacing surface, said interface surfaces of each coupling segment having an angular orientation opposite to each other, The interfacing surface of the first coupling segment contacts a corresponding interfacing surface of the second coupling segment and the first and second coupling segments rotate about a vertical axis in a direction opposite to each other A method for engaging first and second pipe elements in an end-to-end relationship. 28. The method according to claim 27, wherein the pipe coupling is a flexible pipe coupling, the first and second pipe elements being joined in an end-to-end relationship.

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